For each landscaping job that takes more than 4 hours, a certain contractor charges a total of r dollars for the first 4 hours plus 0.2r dollars for each additional hour or fraction of an hour, where r > 100. Did a particular landscaping job take more than 10 hours?

(1) The contractor charged a total of $288 for the job.

(2) The contractor charged a total of 2.4r dollars for the job.


Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

EACH statement ALONE is sufficient.

Statements (1) and (2) TOGETHER are NOT sufficient.

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题目分析：

设绿化工作花费的时间为x小时。

（1） 所以有r+0.2r*(x-4)=288，即3.2r+0.2rx=288，由于不能确定r的值，因此x的值也不能确定，例如，r=120时，x=11，超过了10小时。又如r=160时，x=8，不足10小时，所以条件1不满足要求。

（2） 承包商费用为2.4r，有r+0.2r*(x-4)=2.4r，解得x=11，超过了10小时，题目得解。

因此，本题答案为（B），仅条件2可以解题，条件1不行。

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